The invention relates to a safety attachment device for progression of a user along a handrail, and comprising:                a pair of main progression lanyards each equipped with a means for attaching a snap-hook,        an energy absorber to absorb shocks in case of a fall,        an auxiliary lanyard,        and a fixing means designed to be joined to the user's harness.        
Such devices are used for the safety of people performing pot-holing or climbing in particular on a via ferrata.